1. Field of the Invention
This invention relates to a conversion unit of an outboard motor, particularly to an outboard motor conversion unit attached to an outboard motor in which a steering mechanism or the like is operated by manually manipulating a mechanical operation mechanism installed at a boat, for converting the outboard motor to electronically-operated type.
2. Description of the Related Art
Conventionally, an outboard motor equipped with a so-called mechanical operation mechanism is widely used, in which a steering wheel installed at a boat is connected to a steering mechanism of the outboard motor through a push-pull cable and the like and the outboard motor is steered by transmitting rotation of the steering wheel to the steering mechanism, while a shift/throttle lever installed at the boat is connected to a shift mechanism and throttle valve of the outboard motor through the push-pull cable and the like and shift change or engine speed regulation is conducted by transmitting manual manipulation of the shift/throttle lever to the mechanisms.
Further, in recent years, an outboard motor configured to conduct steering, shift change or engine speed regulation by controlling the operation of actuators connected to a steering mechanism, shift mechanism and throttle valve of the outboard motor, i.e., an electronically-operated outboard motor is proposed as taught, for example, in U.S. Pat. No. 6,910,927.
In the outboard motor disclosed in the prior art, a boat is required to be equipped with a specific operation mechanism. Specifically, it becomes necessary to have an electronic operation mechanism including a steering wheel angle sensor installed near a steering wheel for outputting a driving signal to the actuator of the steering mechanism so as to establish steering angle detected by the steering wheel angle sensor and a lever position sensor installed near a shift/throttle lever for outputting a driving signal to the actuator of the shift mechanism or throttle valve so as to achieve a shift position or engine speed corresponding to the lever position detected by the lever position sensor.
In order to change a mechanically-operated outboard motor to an electronically-operated one, a remote control unit or the like designed for the electronically-operated outboard motor and having an electronic operation mechanism is needed to be newly installed near the operator's seat of the boat. In that case, since the outboard motor can be steered with the remote control unit, the hitherto-used mechanical operation mechanism becomes unnecessary. Thus, when an outboard motor equipped with a mechanical operation mechanism is changed to an electronically-operated outboard motor, it is necessary to replace the mechanical operation mechanism with the remote control unit, making the changing procedure inconvenient.